Automatic water shut off system to prevent overflow of a plumbing device

ABSTRACT

A control circuit for a plumbing device that has a drain line and a water supply line includes a water sensor generating a potential overflow level signal in response to the water level in the plumbing device caused from a restricted drain line, an electrically controlled valve coupled to the drain line, and a controller coupled to the water sensor and the valve. The controller closes the valve in response to the potential overflow level signal.

[0001] The present invention claims priority to U.S. provisionalapplication No. 60/395,512, filed on Jul. 12, 2002.

TECHNICAL FIELD

[0002] The present invention relates generally to plumbing devices, andmore particularly to a system for preventing the overflow of theplumbing device.

BACKGROUND ART

[0003] The damage caused from the overflow of plumbing devices can bevery expensive. Plumbing devices such as toilets and bathtubs mayoverflow if their drains are plugged. Damage can be multiplied if thedevices are in multi-unit dwellings, since the damage may extend severalfloors below. A typical device has a supply line that provides waterthereto. Typically, the water supply continues to operate even if amalfunction such as a plugged drain is present.

[0004] A system for controlling the operation of a toilet is describedin U.S. Pat. No. 5,731,758. In this patent, several sensors are locatedwithin the toilet tank for detecting the level of water therein. Whenthe water reaches a shut off level within the tank, the supply line isshut off. This system is meant to replace the ball float-type systems ina toilet. Although the system illustrates a floor water probe,overflowing water from the bowl is not shut off until detected by thesensor 22. Thus, some leakage does occur in the '758 patent allowing forthe potential for damage.

[0005] It would therefore be desirable to provide a device that shutsoff the water supply to a plumbing device prior to overflowing of theplumbing device.

SUMMARY OF THE INVENTION

[0006] The present invention provides an overflow shut off controlcircuit for a plumbing device.

[0007] In one aspect of the invention a control circuit for a plumbingdevice that has a drain line and a water supply line includes a watersensor generating a potential overflow level signal in response to thewater level in the plumbing device caused from a restricted drain line,an electrically controlled valve coupled to the drain line, and acontroller coupled to the water sensor and the valve. The controllercloses the valve in response to the potential overflow level signal.

[0008] A control circuit for a toilet assembly having a toilet bowlhaving a rim and a water supply includes a water sensor disposedadjacent to the rim. The water sensor generates a water level signal inresponse to the water level in the bowl.

[0009] In yet another aspect of the invention a method of operating aplumbing device includes the steps of detecting a potential overflowfrom a plumbing device, and closing a valve in a supply line in responseto the step of detecting.

[0010] One advantage of the invention is that property damage to acontinually operating plumbing device is reduced. Such a device would beparticularly useful in multi-unit dwellings. Another advantage is thatif the plumbing device is defective such as a bad flap valve, thepresence of water will cause the flow of water to be stopped. This alsosaves water.

[0011] A further advantage of the invention is that natural resourcessuch as water are reduced in the operation or failure of the plumbingdevices.

[0012] Other aspects and advantages of the present invention will becomeapparent upon the following detailed description and appended claims,and upon reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013]FIG. 1 is a perspective view of a toilet having a shut off controlcircuit according to the present invention.

[0014]FIG. 2 is a partial cross-sectional block diagrammatic view of acontrol circuit according to the present invention.

[0015]FIG. 3 is a block diagrammatic view of the control circuitaccording to the present invention.

[0016]FIG. 4 is a perspective view of a water heater having a circuitaccording to the present invention.

[0017]FIG. 5 is a perspective view of a bathtub having a control circuitaccording to the present invention.

BEST MODES FOR CARRYING OUT THE INVENTION

[0018] In the following figures the same reference numerals will be usedto identify the same components.

[0019] While a limited number of plumbing devices such as a toilet,water heater and bathtub are illustrated, the present invention mayapply to other types of plumbing devices.

[0020] Referring now to FIG. 1, a plumbing device 10 is illustrated as atoilet 12 that has a tank 14 and a toilet bowl 16. The toilet tank has asupply line 18 that supplies water to the tank 14. A drain line 20 isused to remove waste from the toilet bowl 16. A shut off control circuit22 is illustrated coupled to a sensor 24. Shut off control circuit 22 isused to close the supply line 18 to prevent supply water from reachingtank 14. A control circuit 22 operates in response to sensor 24detecting a level of water that may cause an overflow of the toilet bowl16.

[0021] Referring now to FIG. 2, toilet 12 and control circuit 22 areillustrated in further detail. Toilet bowl 16 has a rim 26 and seat 28.

[0022] Control circuit 22 includes an electrically operated valve suchas a solenoid operated shut off valve 30. Preferably, shut off valve 30is normally open so that water freely flows through supply line 18. Ofcourse the shut off valve could be normally closed. Solenoid operatedvalve 30 is operated in response to a controller 32. Controller 32 maybe microprocessor-based. Controller 32 may also be formed of discretecircuitry. Various types of control circuits would be evident to thosein the art. Controller 32 is coupled to sensor 24 used to sense thelevel of water within toilet bowl 16. Sensor 24 is preferably positionedadjacent to rim 26 not touching or away from the sides of the bowl in aposition at or above the normal water level 34. This allows preventionof the overflow of the toilet bowl 16. Thus, sensor 24 generates apotential overflow level signal in response to the level of water withinthe toilet bowl 16 that corresponds to a potential for overflow. Whenthe level reaches sensor 24, the circuit is continued through the sensor(continuity) to indicate a restricted drain line 20 shown in FIG. 1. Thesensor 24 may also be integrally formed within toilet bowl 16 orpositioned between seat 28 and rim 26 in an aftermarket typeapplication. Controller 32 may be disposed on a circuit board 36.

[0023] Solenoid operated shut off valve 30 may also include manuallyoperated levers 38 to turn on the flow of water to the plumbing device.Levers 38 allow the solenoid operated valve to be open if power isdiscontinued from the device such as in a power failure.

[0024] Referring now to FIG. 3, a block diagrammatic view of shut offcontrol circuit 22 is illustrated. Shut off control circuit 32 may havea central controller and a central power supply 40. The shut off controlcircuit 22 may include a common controller 32 and a power supply 40 fora number (n) of sensors 24 a-25 n and a number (n) of shut off valves 30a-30 n. The various sensors 24 and shut off valves 30 may be associatedwith various types of plumbing devices such as toilet-type devices suchas a toilet, urinal or bidet. For example, in a commercial applicationboth men and ladies restrooms may include several sensors and severalshut off valves that use a central controller 32 and power supply 40.

[0025] The power supply 40 may, for example, be a 24-volt DC source.Such a source is transformed down from the power source from thebuilding. Those skilled in the art will also recognize various types ofsolenoids using various types of power supplies may also be incorporatedinto the device.

[0026] Controller 32 may also be coupled to an alarm 42 that generatesan audible or visual alarm in response to the level of water in theplumbing device. In addition, controller 32 may be coupled to an alarmsystem interface 44. Alarm system interface 44 may act to notify acentral controller so that help may be dispatched from a centralmonitoring system.

[0027] In operation, the sensors upon sensing a level of water thatcontacts sensors 24, a valve 30 is shut off by shut off control circuit22.

[0028] Referring now to FIG. 4, a hot water tank 50 is illustratedhaving a shut off control circuit 22 and sensor 24 formed according tothe present invention. Thus, as sensor 24 detects the presence of waterin a pan 52 positioned beneath hot water tank 50, sensor 24 initiatesthe shut off of supply line 18 through shut off control circuit 22.

[0029] Referring now to FIG. 5, a bathtub 56 is illustrated. Bathtub 56has a rim 58 disposed thereon. A sensor 24 is positioned adjacent to rim58 within the bathtub 56. Shut off control circuit 22 may operate twocontrol valves 30A, 30B in response to one sensor 24. This allows boththe hot and cold supply lines 18 a and 18 b to be shut off to preventoverflow of bathtub 56.

[0030] As can be seen above, various advantages of the invention areinherent in such device. First, the reduced amount of water or no waterdue to a malfunctioning plumbing device is present. Second, because ofthe reduced amount of water the damage associated therewith,particularly in multi-unit dwellings, is substantially reduced.

[0031] As mentioned above, another advantage is that if the plumbingdevice is defective such as a bad flap valve for a toilet, the presenceof water leaking into the bowl may be detected by the sensor. Thepresence of water will cause the supply of water to the toilet tank bestopped. This also saves water and may alert the premises owner to thedefect while reducing the amount of water used and reducing the waterbill.

[0032] Those skilled in the art will also recognize that various othertypes of plumbing devices such as laundry tubs, sinks, washing machinesand the like may also benefit from the present invention.

[0033] While the invention has been described in connection with one ormore embodiments, it should be understood that the invention is notlimited to those embodiments. On the contrary, the invention is intendedto cover all alternatives, modifications, and equivalents, as may beincluded within the spirit and scope of the appended claims.

What is claimed is:
 1. A control circuit for a plumbing device having adrain line and a water supply line comprises: a water sensor generatinga potential overflow level signal in response to the water level in theplumbing device caused from a restricted drain line; an electricallycontrolled valve coupled the supply line; and a controller coupled tothe water sensor and the valve, said controller closing the valve inresponse to a potential overflow level signal.
 2. A control circuit asrecited in claim 1 wherein the water sensor is an electrical watersensor.
 3. A control circuit as recited in claim 1 wherein said watersensor is disposed within a plumbing device.
 4. A control circuit asrecited in claim 1 wherein said water sensor is disposed adjacent to theplumbing device.
 5. A control circuit as recited in claim 1 wherein saidwater sensor comprises a continuity sensor.
 6. A control circuit asrecited in claim 1 wherein said valve has a manually operated override.7. A control circuit as recited in claim 1 wherein the plumbing devicecomprises a plurality of plumbing devices and said water sensorcomprises a plurality of water sensors.
 8. A control circuit as recitedin claim 1 further comprising an alarm coupled to said controller, saidalarm operated in response to said potential overflow level signal.
 9. Acontrol circuit as recited in claim 1 further comprising an alarminterface coupled to said controller, said alarm interface operated inresponse to said potential overflow level signal.
 10. A control circuitfor toilet assembly having a toilet bowl and a water supply linecomprising: a water sensor disposed within the bowl, said water sensorgenerating a water level signal in response to the water level in thebowl; an electrically controlled valve coupled the supply line; and acontroller coupled to the water sensor and the valve, said controllercontrolling the valve in response to the water level signal.
 11. Acontrol circuit as recited in claim 10 wherein the water sensor is anelectrical water sensor.
 12. A control circuit as recited in claim 10wherein said water sensor comprises a continuity sensor.
 13. A controlcircuit as recited in claim 10 wherein said valve has a manuallyoperated override.
 14. A control circuit for a hot water tankcomprising: a water supply line; a water sensor generating an overflowlevel signal in response to the water level adjacent to the hot watertank; an electrically controlled valve coupled the supply line; and acontroller coupled to the water sensor and the valve, said controllerclosing the valve in response to the overflow level signal.
 15. Acontrol circuit as recited in claim 14 wherein the water sensor is anelectrical water sensor.
 16. A control circuit as recited in claim 14wherein said water sensor comprises a continuity sensor.
 17. A controlcircuit as recited in claim 14 wherein said valve has a manuallyoperated override.
 18. A method of operating a plumbing devicecomprising: detecting a potential overflow from a plumbing device; andclosing a valve in a supply line in response to the step of detecting.19. A method as recited in claim 18 wherein detecting comprisesdetecting a potential overflow in a toilet bowl.
 20. A method as recitedin claim 18 further comprising manually opening the valve.